HP E1411A, Руководство по обслуживанию

Страница: 78 / 78

Resistance
Adjustments
This example performs a 4-wire ohms resistance adjustment for a power
line reference frequency of 60 Hz. If a calibration error occurs, the program
displays the calibration error and prompts you to repeat the adjustment (see
Table 5-1 for a list of calibration errors).
/* 4-wire Resistance Adjustments E1411A/B */
#include <stdio.h>
#include <sicl.h>
#define ADDR "hpib7,9,03" /* Address of device */
void main ()
{
INST id; /* Define id as an instrument */
float range[3] = {2000, 16000, 1048576};
float source[3] = {1000, 10000, 1000000};
char cal_code[5][256];
float actual[3];
int i;
#if defined(__BORLANDC__) && !defined(__WIN32__)
_InitEasyWin();
#endif
ionerror(I_ERROR_EXIT); /* Exit on error */
id = iopen (ADDR); /* Open instrument session */
iprintf (id, "*RST\n"); /* Resets and set autozero
ON and PLC to 1 */
iprintf (id, "CAL:LFR 60\n"); /* Sets line reference to 60 Hz */
for(i = 0; i 3; i++) /* Take voltage measurements */
{
retry:
printf("\n Set Resistance Standard to %.1f Ohms", source[i]);
printf("\n Measure ACTUAL Resistance Standard value (in
Ohms):");
scanf ("%f", &actual[i]);
iprintf(id, "FUNC:FRES\n"); /* Set DCV function */
iprintf(id, "FRES:RANG %f\n", range[i]); /* Set E1326B range */
iprintf(id, "CAL:VAL %f\n", actual[i]); /* Set CAL:VAL value */
ipromptf(id, "CAL?\n", "%t", cal_code[i]); /* Read voltage */
if (cal_code != 0)
{
printf ("\nCalibration Error %s for %f Ohms", cal_code,
source[i]);
printf ("\nCheck source value/connections, then");
printf ("\npress ENTER to retry this adjustment");
getchar ();
goto retry;
}
else
printf ("\nAdjustment complete with %f Ohms source\n",
source[i]);
}
iclose (id); /* Close instrument session */
}
78 Verification Tests - C Programs Appendix B